Allosteric targeting is progressively gaining ground as a strategy in drug design. Its success, however, depends on our knowledge of the investigated system. In the case of the papain-like cysteine peptidase cathepsin K, a major obstacle in our understanding of allostery is represented by the lack of observable conformational change at the active site. This makes it difficult to understand how ...

Papain is a proteolytic enzyme of great commercial value. It cysteine protease highly expressed in Carica papaya fruit latex, but also present leaves. Purification procedures mostly deal with the latex and include combination precipitation and/or chromatographic techniques. Due to its solubility, structure activity characteristics, pH salt content play significant roles handling papain extracts...

The significant role of papain-like cysteine proteases, including papain, cathepsin L and SARS-CoV-2 PLpro, in biomedicine biotechnology makes them interesting model systems for sensor development. These enzymes have a free thiol group that is suitable many designs strong binding to gold nanoparticles or low-molecular-weight inhibitors. Focusing on the importance preservation native protein str...

BACKGROUND The objective of this study was to verify the hypothesis that enamel deproteinization with papain gel at concentrations of 2%, 4%, 6%, 8%, and 10% increases shear bond strength as concentration increases. METHODS A total of 180 bovine mandibular permanent incisors were used, divided into six groups (n=30), and denominated as follows: group 1 is the control group (CG) in which brack...

Leupeptin and similar peptide argininal (arginine aldehyde) transition-state analog protease inhibitors exist in three covalent forms in aqueous solution, the leupeptin hydrate (IH), a cyclic carbinolamine form (IC) generated by the addition of the guanidino epsilon N to the aldehydic carbon, and the free aldehyde form (IA). 1H NMR in D2O show their equilibrium concentrations to be 42, 56, and ...

We have investigated the inhibition of the recently identified family C13 cysteine peptidase, pig legumain, by human cystatin C. The cystatin was seen to inhibit enzyme activity by stoichiometric 1:1 binding in competition with substrate. The Ki value for the interaction was 0.20 nM, i.e. cystatin C had an affinity for legumain similar to that for the papain-like family C1 cysteine peptidase, c...

BACKGROUND Particulate systems have received increasing attention for oral delivery of biomolecules. The objective of the present study was to prepare submicron particulate formulations of papain for pH-dependent site-specific release using pH-sensitive polymers. METHODS Enteric submicron particle formulations of papain were prepared by w/o/w emulsion solvent evaporation using hydroxypropyl m...

BACKGROUND The safe transfusion of patients with warm autoimmune hemolytic anemia requires an efficient and time-saving assay to detect alloantibodies underlying autoantibodies. Methods used include RBCs treated with ZZAP reagent, proteolytic enzyme, or untreated RBCs in the presence of PEG. We propose a method using LISS, which presents some advantages over previous methods. STUDY DESIGN AND...

Effect of lower concentrations of urea on papain was monitored by optical spectroscopy, calorimetry and partial specific volume measurements. At lower concentrations of urea, papain exhibits a different structure and showed an increase in the intensity of circular dichroic (CD) spectra as compared to the native molecule. At lower concentrations (0.2-1.5 M) of urea, binding of 8-anilino-naphthal...

Allergic diseases, including asthma, are characterized by T helper type 2 (Th2) cell-mediated inflammations, coupled with tissue infiltration by eosinophils. In this study, we demonstrate that multiple protease allergens, including papain and DerP1, efficiently induce interleukin (IL)-25 and thymic stromal lymphopoietin (TSLP) gene expression, and this phenomenon is dependent on the protease ac...